Jeremy Paxman bowed out of Newsnight after 25 years with a parting joke, bringing his sardonic style to a spoof presentation of the weather.

His final show saw Boris Johnson become the last person to face the veteran broadcaster's abrasive interviewing technique, but the London mayor had only warm words to say about him.

As he signed off the BBC2 programme for the final time last night, Paxman told viewers: "I'll just say thank you for watching Newsnight. I hope you continue to enjoy it. Goodnight and goodbye."

The closing credits were accompanied by the The New Seekers' I'd Like To Teach The World To Sing before the spoof - a nod to a weather report he previously introduced with the words: "And for tonight's weather - it's April, what do you expect?"

Last night, he appeared in front of a large map of the country with the final words: "And tomorrow's weather - more of the same. I don't know why they make such a fuss about it."

Earlier in the programme - which also saw Paxman grill Labour peer Lord Mandelson on Iraq - viewers were treated to a more light-hearted pre-recorded segment featuring the presenter cycling around London with the mayor on a tandem.

Mr Johnson told Paxman he was "a landmark of our culture" while members of the public were heard in the background shouting at the pair, prompting Paxman to ask the mayor if people often shouted at him.

"Normally they shout, 'You Tory tosser'," Johnson replied.

The mayor went on to say: "This is Jeremy's valedictory programme, and I just want to say on behalf of Jeremy's many many admirers, that there will be a lot of people who are very sad to see you go.

"Because he has kept the nation entertained - if not always awake - for many, many years and has been an adornment to broadcasting."

Paxman announced his departure from BBC2's flagship current affairs show in April, saying he wanted to "go to bed at much the same time as most people".

In his final programme he found the tables were turned when he was interviewed by Jon Snow on Channel 4 News.

Asked about Newsnight's future, Paxman said: " I hope it's going to go on for years. No programme has a God-given right to exist forever, of course.

"There comes a point in the life of old codgers where they've got to give up. Of course I'll miss it - working with lots of clever and talented people. And having a laugh."

He said he had wanted to leave before he got to the point where his colleagues might say: " I wonder if that old bugger's going to get the wrong end of the stick tonight."

He described the BBC as a "noble, noble ambition and enterprise" but admitted that he hated the new Broadcasting House.

And quizzed on why he does not use Twitter, he told Snow: " I have no thoughts that I want to share with people. I don't want anyone to follow me.

"As far as I can see this is an activity for people who have got nothing going on between their ears, or nothing going on in their lives."

Paxman's terrier-like approach, often complete with a condescending raised eyebrow at the subsequent answer, did not always make him popular with guests but made Newsnight a hit.

Paxman, whose BBC biography says he got his break in broadcasting "making the tea at Radio Brighton", has spent his working life with the corporation.

His career includes a stint covering the troubles in Northern Ireland and working as a presenter on radio, breakfast TV and the Six O'Clock News before finding the show he made his own.

The Leeds-born broadcaster, who studied at Cambridge University, is the author of a string of books including studies of Victorian Britain, politics and fishing, and will continue to host quiz show University Challenge.